This invention is in the field of security and access control, and the invention particularly concerns access to door locks and other situations wherein numerous mechanical keys fit a single or a group of locks and wherein there is a need to control the instances of opening each lock and in some situations to maintain a record thereof.
In the past, a number of electronic security features have been added to mechanical locks which use mechanical types of cylinders. In addition, locking elements controlled by electronic means have been disclosed in combination with non-mechanical types of tumblers, such as in Clarkson et al. U.S. Pat. No. 4,712,398. In some cases electronic elements have been added to mechanical elements requiring both mechanical and electronic elements to be present before granting access such as Spahn et al. U.S. Pat. No. 5,469,727. Some of the existing electronic systems have employed keypads, some have employed cards, some have had purely electronic, magnetic or optical access control devices, and some have employed mechanical keys equipped with electronic circuitry.
With respect to the present invention, distinction is made among purely electronic, magnetic or optical keys; mechanical keys equipped with electronic, magnetic or optical features; and mechanical keys which operate solely by mechanical bittings, whether those bittings be pin tumbler, dimples or other mechanical patterns.
A key comprised of purely electronic circuitry, magnetic or optical data storage for determining and granting access is an electronic key. In the use of such a key, the circuitry or recorded data is transferred to a reader associated with a lock, and the reader recognizes a pattern or code held by the key. The key does not carry any mechanical cut or bitting configuration needed for granting access even though the key holding the data or the pattern may be used for turning the lock. Keys of this type can be found in U.S. Pat. No. 3,797,936 (Dimitriadis), U.S. Pat. No. 4,209,782 (Donath et al.), U.S. Pat. No. 4,257,030 (Bruhin et al.), U.S. Pat. No. 4,620,088 (Flies), U.S. Pat. No. 4,659,915 (Flies) and U.S. Pat. No. 4,789,859 (Clarkson et al.).
Keys referred to as mechanical keys are those which activate a mechanical device, with a pattern of mechanical bittings, by direct contact with the interpreting device, i.e. the tumblers or other pattern-holding apparatus contained in the lock. In a typical pin tumbler lock, access is granted based on the depth and configuration of key cuts meeting the tumblers. In most cases, once proper alignment is established in the tumblers, the keyholder is able to turn the key to lock and unlock the locking device. However, in some cases of mechanical keys, a push or pull action may be necessary for locking and unlocking of the device. The tumblers mentioned above can be pin tumblers, lever tumblers, disk tumblers, rotary disk tumblers, slider tumblers, or combinations of several of these incorporated within the same lock. Examples of purely mechanical keys are found in U.S. Pat. No. 480,299 (Voight), U.S. Pat. No. 550,111 (Sargent), U.S. Pat. No. 564,029 (Sargent), U.S. Pat. No. 3,208,248 (Tornoe), U.S. Pat. No. 4,723,427 (Oliver), U.S. Pat. No. 4,732,022 (Oliver) and U.S. Pat. No. 4,823,575 (Florian et al.).
Examples of mechanical keys equipped with electronic circuitry, magnetic or optical data storage or optical recognizable features ("mechanical/electronic keys`) can be found in U.S. Pat. No. 3,733,862 (Killmeyer), U.S. Pat. No. 4,144,523 (Kaplit), U.S. Pat. No. 4,326,124 (Faude), U.S. Pat. No. 4,562,712 (Wolter), U.S. Pat. No. 4,663,952 (Gelhard), U.S. Pat. No. 4,686,358 (Seckinger et al.), U.S. Pat. No. 5,245,329 (Gokcebay), U.S. Pat. No. 5,367,295 (Gokcebay et al.) and U.S. Pat. No. 5,140,317 (Hyatt, Jr. et al.). Such keys carry the secondary element, whether it comprises electronic circuitry or some other type of coded data or recognizable pattern, in addition to the key's mechanically operating pattern or bitting. In some instances both mechanical and non-mechanical features of a key are used simultaneously.
A lock cylinder is the control mechanism which grants access to the lock. A mechanical lock cylinder is the control mechanism which grants or denies access to the lock based on the mechanical key being used. The mechanical configuration, i.e. the cuts on the key, has to match to the meeting mechanical configuration i.e. the tumblers of the cylinder before the key will turn in the cylinder and this turning motion will engage the latch or bolt mechanism of the lock via a cylinder cam or tail piece causing the locking or unlocking of the lock. The cylinder mechanism of the lock is generally a separate module which can be easily removed and replaced. In certain types of locks the physical characteristics of the cylinders and their receiving cavity is standardized so one brand cylinder will fit or replace another brand of cylinder. Mortise, locks using mortise (regular or removable core) or profile cylinders (eurocylinder) and rim locks using rim cylinders are good examples. The cylinder size and shape differ on bored door locks such as knob locks and deadbolt locks. Thus, one can separate the mechanical lock cylinders into two categories, those that are standard in size and shape, and those that are brand specific. With the standard cylinders one brand cylinder will replace another instantly without any modification to the lock, door or the cylinder.
There are several cylinder manufactures who specialize in making replacement cylinders which fit in other brands of locks. In some cases these are specialized high security cylinders increasing the security of the lock by offering sophisticated locking principles and key control. Also several lock manufacturers have recently started to manufacture non standard (brand specific) cylinders that fit to their competitors' locks. This is generally a marketing issue wherein by making cylinders that fit into the competitors' locks and setting up key systems using their own keyway (grooving and slotting of the key and receiving plug, they lure the customer to buy their locks for future needs. Since in order for the new locks to fit in to the keying system they need to be the same keyway, the customer opts to buy their brand of lock for future use.
It has been desirable to add electronic security and access control features to mechanical locks since, for one thing, it is not possible to regulate the date, day and time of access using purely mechanical keys and meeting tumblers. Changing the combination of a lock when a key is compromised usually requires tumblers to be changed and all of the operating keys to be replaced which is costly. Also the number of unique combinations or permutations that can be achieved using purely mechanical keys and meeting tumblers is relatively low, and further security is often needed.
Many examples of purely electronic and electronic and mechanical combinations of control elements exist in the above referenced patents. Only a few of these inventions teach an instant replacement of the cylinder unit to fit to existing locks without further modification to the lock or the door. In most cases the cylinder unit acting as an electronic reader, having additional parts or components that are connected by wires to other parts of the lock or the door, requires modification of the door and/or the lock. These components generally are circuit boards containing decision making electronics, batteries and electrically operated locking elements such as solenoids and motors. Providing a cylinder having electronic features that offers instant replacement to fit existing locks that work with a standard type of mechanical cylinders is desirable since there are millions of existing locks that can be easily retrofitted with the cylinders of these products. The prior art does not disclose a self contained cylinder wherein the cylinder is operated by a mechanical key with electronic features and electronic or electronic plus mechanical features of the key are relied on for access. These disclosed prior devices are operated by purely electronic keys (at times shaped like a conventional mechanical key) and do not offer mechanical key configuration on the key as an additional criteria for access or to be used on other mechanical only cylinders. Relying on the mechanical configuration of the key in addition to the electronic criteria is desirable because this offers additional security. Relying on the electronic criteria only of the key is sometimes also desirable as it provides flexibility. In a facility not all doors may require access control i.e. regulating time and day of the entry. These doors may be operated by only the mechanical criteria of the key, not relying on the electronic criteria. It is also desirable because as mentioned above, installation of the electromechanical cylinders brings in sales of mechanical-only locks using the same keyway configuration used in the electromechanical cylinder.
Of those patents disclosing standard replacement cylinder units, Clarkson et al. U.S. Pat. No. 4,712,398 shows a cylinder operated by entirely electronic criteria. The key "which closely resembles a traditional mechanical key without the usual bittings" contains electronic circuitry or memory in the key blade, which when inserted into the receiving cylinder, operates the cylinder if the data contained in the key matches the data stored in the receiving cylinder, by actuation of an electrically operated locking mechanism in the cylinder. Although there is one pin inside the cylinder and a single cut in the key, it is not used or relied on for granting access. It is used for centering and retention. All keys of the system have the same cut and all cylinders have the same pin, thus showing that no differentiation can be made between the keys requesting access based on mechanical configuration of the key. Clarkson employs a complicated communication scheme where the electronic identifying code is located on the key blade. Upon insertion of the key blade into the cylinder the key makes contact with its contact points "key connectors" to the cylinder's contact points "cylinder connectors" by brushing against each other to transfer the data from the key. Since the key electronics are located on the key blade itself, it is not possible to place a keyway profile (milling a grooving configuration) or cuts on the key.
Another similar system although not self contained disclosed in Chhatwal U.S. Pat. No. 5,337,588 (and also Chhatwal U.S. Pat. No. 5,507,162) employs an opto-electronic communication between the lock and the key for transmitting data contained in the key to the cylinder for requesting access. In addition the key makes physical contact with the cylinder unit via an isolated contact on the key blade to power the key electronics. The decision making electronics are located outside the cylinder and connected to the cylinder via a cable. Again the cylinder disclosed has a single pin which is used for alignment purposes. The physical size or shape of the pin and or matching cut in the key is not used for differentiating keys from one another, thus not constituting a mechanical key.
A cylinder disclosed by Spahn et al. U.S. Pat. No. 5,469,727 requires both mechanical and electronic elements to be present before granting access; however, the electronic circuitry and the power source are housed elsewhere in the lock and door and wired to the cylinder, requiring additional modification to the door and the lock, and thus defeating the purpose of instant replacement of a standard cylinder.
U.S. Pat. No. 5,140,317, Hyatt Jr. et al. also referenced above, discloses a combined mechanical lock/key combination which further includes an electronic feature for permitting opening of each lock in a system of similarly-keyed locks, only when authorized, and with a recording of each lock opening made. Although the system is not for locks using standard cylinders it is an example of prior art using both mechanical and electronic elements for granting access. The system disclosed in the patent includes a mechanical key with a key cut configuration, and with means for making electrical contact with electronics inside the lock. A separate box carried by the keyholder is connected by electric wiring to the key, the box including a keypad, a microprocessor, a battery for powering the system and the lock, and a memory with stored data. The lock includes a retractable blocking means which blocks opening of the lock's bolt, separately from the mechanical bitting, except when prescribed conditions are met. When a solenoid in the lock is activated the blocking means is retracted. The lock also includes its own microprocessor, which controls switching of power to the solenoid, and with a memory within the lock storing data. The microprocessor within the lock compares coded data read from the key with coded data in the memory within the lock, and thus controls powering of the solenoid to situations in which a comparison, made within the lock's microprocessor, determines that coded data read from the key matches coded data in the lock's memory. The key (i.e. the separate box connected to the key) provides power to the lock's solenoid to allow access. Also, the lock's microprocessor further calculates a new code for the lock, after each opening of the lock.
The above patent is applicable to coin locks and other situations wherein a mechanical key has bitting matched to a large number of similar locks, but where control of the opening of each lock is desired, and where a record is needed of each lock's opening. The system has been applied to pay telephone coin boxes. However, as noted, the system requires a separate box connected by electric wiring to the key, the box containing the equipment noted above. The system is thus unsuitable for applications wherein the key is used to access doors of a building or home as carrying a key along with a box is unacceptable. As stated above the system of the patent also requires additional hardware within the lock casing which defeats the purpose of instant replacement. In addition, considerable modification in retrofitting of existing locks is required, increasing cost of implementing the system, in addition to high cost of manufacture and materials.
A system described by the present applicant in U.S. Pat. No. 5,552,777, incorporated herein by reference, shows a lock system also applicable to coin locks and other situations wherein a mechanical key has bitting matched to a large number of similar locks, but where control of the opening of each lock is desired, and where a record is needed of each lock's opening. This is an example of prior art using both mechanical and electronic elements of the key for granting access. The power, keypad, microcontroller and memory required for systems operation are incorporated into the key. This eliminates carrying of a box attached to the key. In addition the system of the patent also eliminates use of a microcontroller in the lock and combines the blocking means (solenoid) and the entire circuitry within the plug of a lock cylinder which allows instant replacement to existing locks as the lock described in the patented system is same size as the one it replaces. The key described in the U.S. Pat. No. 5,552,777 patent containing the keypad, microprocessor, memory and power source, although much smaller than the apparatus described by U.S. Pat. No. 5,140,317 (Hyatt, Jr. et al.), is still generally too large for applications wherein the key is used to access doors of a building or home.
It is an object of the invention described below to provide a self contained electromechanical lock cylinder which is the same size as its mechanical-only replacement and therefore easily retrofitted into existing locks used in doors of a building wherein a number of keys operate one or a number of locks, and which avoids the need for electronics, solenoids or other hardware which would take up space within the door, the lock casing or attached to the door adjacent to the lock. The lock is operated by a small size mechanical key carrying electronic properties, wherein the key is not larger than an ordinary car key and the mechanical and electronic properties of the key can be used simultaneously, or the electronic properties only can be used at some locks to grant access while the mechanical properties can be relied on for access at other doors where mechanical-only cylinders are used. In additional aspects of the invention, it is an object to provide an access control system wherein the lock cylinders are programmable with the valid operating keys, in addition limiting the times and dates of the keys' operation as well as providing means for some of the keys to work only a set number of times, and in another embodiment, to record each instance of access to a lock, by key number, in the situation of a lock accessible by a number of different keys. Another object of the invention is to provide easy to use programming methods for programming the cylinders.